The present invention relates generally to industrial control systems, and, more particularly, to security layers for a wireless industrial control user interface.
Industrial controllers are special purpose computers used for controlling industrial processes or manufacturing equipment. Under the direction of a stored program, the industrial controller examines a series of inputs reflecting the status of the controlled process and changes outputs affecting the control of the process. The inputs and outputs may be binary (i.e., “on” or “off”) or analog taking on a continuous range of values. The binary inputs and outputs may be represented by single bits of data, the analog inputs and outputs may be represented by multiple bit data words.
Exemplary applications for industrial control systems include material handling, robotics, airport baggage handling, water and wastewater treatment, cement production, semiconductor fabrication, electric power, entertainment, food processing, mining, beverage and packaging operations, ski lift operations, forest products processing, life sciences, logistic processes, fibers and textiles processing, metal forming, automotive, petroleum and chemical processing, plastics processing, automated transportation, health care, agriculture, postal and shipping, and other manufacturing processes, to name but a few examples.
The various components of an industrial controller are often spatially distributed about a factory or manufacturing facility to be interconnected by one or more communication networks. These communication networks are characterized by being highly reliable and by delivering data with a minimal and well defined delay, as is required for real-time control. A number of different communication networks are commonly used in the industrial controller art including but not limited to: ControlNet™; DeviceNet™ and Ethernet/IP™ whose specifications are published and whose protocols are used broadly by a number of manufacturers and suppliers, including Rockwell Automation Inc. of Milwaukee, Wis. These communication networks differ from one another in physical aspects, for example, the type of media (e.g., co-axial cable, twisted pair, light fiber, etc.); the protocols of its operation, (e.g., Baud rate, number of channels, word transmission size, use of connected messaging, etc.) and how the data is formatted and how it is collected into standard messages.
At the site of an industrial control system, it may be possible to gain access to entities within the industrial control system by using a user interface associated with one or more of the automation devices that forms the industrial control system. For example, an individual may use a user interface directly coupled to a motor drive to gain access to the motor drive. Alternatively, standard interfaces are sometimes provided that allow access to be gained by connecting a laptop or other computer to a communication network that connects portions of the industrial control system.
Connecting a user interface to the communication network that allows access to multiple entities within the industrial control system may give rise to security issues and identification accuracy issues. Typically, a device on the communication network, such as an Ethernet network, has access to and can be accessed by any other device on the network. One or more devices on the communication network may have direct or indirect connections with the Internet. As such, an outside entity may try to compromise the user interface, and potentially the industrial control system.
Also, because the user interface may be used to access multiples drives, controllers, I/O modules, etc. within the industrial control network, it may be possible for a user to inadvertently connect to the wrong entity. Previously, this vulnerability has been addressed by requiring proximity to the controlled device (i.e., by requiring a hardwired connection). As wireless networking systems proliferate, it is no longer workable to require hardwired connections to guard against such identification errors.
In the case where a portable user interface is used, it is useful to employ common hardware and software for ease of configuration management. However, from a security and reliability standpoint, it would not be desirable to provide all users of such a portable interface equal access to all functionalities of the industrial control system. For example, an operator may find it useful to access control (e.g., start, stop) and status information regarding a particular motor drive, while a maintenance technician or engineer may need to access the motor drive to update its firmware or change its configuration. If all users were provided a common portable user interface with common functionality, users may intentionally or inadvertently access functionalities for which they lack the requisite training or authority.
This section of this document is intended to introduce various aspects of art that may be related to various aspects of the present invention described and/or claimed below. This section provides background information to facilitate a better understanding of the various aspects of the present invention. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art.